SUBSTRATE PROCESSING METHOD AND SUBSTRATE PROCESSING APPARATUS

• US 20120080408A1
• Filed: 03/18/2011
• Published: 04/05/2012
• Est. Priority Date: 09/30/2010
• Status: Active Grant

• Current Assignee: Kioxia Corporation
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: UI, Akio, Hayashi, Hisataka
• Granted Patent: US 8,821,744 B2
• Time in Patent Office: Days
• US Class Current: 216/71
• CPC Class Codes: H01J 37/32082 Radio frequency generated discharge H01J37/32357, H01J37/32366, H01J37/32394 and H01J37/32403 take precedence
• CPC Class Codes: H01J 37/32146 Amplitude modulation, includes pulsing
• CPC Class Codes: H01J 37/32174 Circuits specially adapted for controlling the RF discharge
• CPC Class Codes: H01L 21/31116 by dry-etching

Abstract

A substrate processing method using a substrate processing apparatus includes a first step and a second step. The first step is to apply a negative voltage pulse from a pulsed power supply to be included in the apparatus. The second step is to apply floating potential for an interval of time between the negative voltage pulse and a positive voltage pulse from the pulsed power supply subsequent to the negative voltage pulse. In addition, the apparatus includes a chamber, a first electrode, a second electrode, an RF power supply, and the pulsed power supply. The second electrode is provided so that the second electrode faces the first electrode to hold a substrate. The RF power supply applies an RF voltage having a frequency of 50 MHz or higher to the second electrode. The pulsed power supply repeatedly applies a voltage waveform with the RF voltage to the second electrode.

Claims

1. A substrate processing method using a substrate processing apparatus, comprising:

a first step of applying a negative voltage pulse from a pulsed power supply to be included in the apparatus; and

a second step of applying floating potential for an interval of time between the negative voltage pulse and a positive voltage pulse from the pulsed power supply subsequent to the negative voltage pulse,

wherein

the apparatus includes;

a chamber;

a first electrode to be provided inside the chamber;

a second electrode to be provided so that the second electrode faces the first electrode to hold a substrate;

an RF power supply to apply an RF voltage having a frequency of 50 MHz or higher to the second electrode; and

the pulsed power supply to repeatedly apply a voltage waveform with the RF voltage to the second electrode, the voltage waveform including a negative voltage pulse and a positive voltage pulse.

2. The substrate processing method according to claim 1, wherein

the pulsed power supply outputs ground potential for an interval of time between a positive voltage pulse and a negative voltage pulse subsequent to the positive voltage pulse, both the negative pulse voltage and the positive pulse voltage being outputted by the pulsed power supply.

3. The substrate processing method according to claim 1, wherein

an interval of time to output the floating potential is 50 ns or shorter.

4. A substrate processing apparatus, comprising:

a chamber;

a first electrode to be provided inside the chamber;

a second electrode to be provided inside the chamber so that the second electrode faces the first electrode to hold a substrate;

an RF power supply to apply an RF voltage having a frequency of 50 MHz or higher to the second electrode; and

a pulsed power supply to repeatedly apply a voltage having a waveform including a negative voltage pulse and a positive voltage pulse to the second electrode with the voltage superimposed on the RF voltage,

wherein

the pulsed power supply includes;

a first power supply to output a first voltage corresponding to a peak voltage of the negative voltage pulse;

a second power supply to output a second voltage corresponding to a peak voltage of the positive voltage pulse;

an output terminal to which any one of the first voltage, the second voltage and ground potential is applied;

a first switch to switch a connection of the first power supply to the output terminal;

a second switch to switch a connection of the second power supply to the output terminal;

a third switch to switch a connection of the ground potential to the output terminal; and

a switching unit to control the first switch, the second switch, and the third switch.

5. The substrate processing apparatus according to claim 4, wherein

the switching unit switches on the first switch and switches off both the second switch and the third switch to allow the pulsed power supply to output the negative voltage pulse to the output terminal;

the switching unit switches off the first switch, the second switch, and the third switch to allow the pulsed power supply to output the floating potential to the output terminal;

the switching unit switches on the second switch and switches off both the first switch and the third switch to allow the pulsed power supply to output the positive voltage pulse to the output terminal; and

the switching unit switches on the third switch and switches off both the first switch and the second switch to allow the pulsed power supply to output the ground potential to the output terminal.